“It’s Cheaper to fix issues in the beginning of any process than at the end.”
Floor, Wall and roof sheathing panels must be spaced 1/8’ apart. Wood expands and contracts with changes in moisture conditions and these gaps are essential in preventing buckling. These gaps acts as small expansion joints and give the panels space to expand as ambient moisture increases.
You can easily create the right spacing by using a 10d nail as a space guide. Always make every effort to keep panels dry but most construction sites will be exposed to moisture during the sheathing process. With the 1/8” spacing, panels can expand without causing buckling or deflection.